836 research outputs found
N=1 Super QCD and Fractional Branes
We show how to get the one-loop beta function and the chiral anomaly of N=1
Super QCD from a stack of fractional N D3-branes localized inside the
world-volume of 2M fractional D7-branes on the orbifold C^3/(Z_2 x Z_2). They
are obtained by analyzing the classical supergravity background generated by
such a brane configuration, in the spirit of the gauge/gravity correspondence.Comment: 4 pages, LaTeX. Talk given at the IXth International Symposium on
Particles, Strings and Cosmology PASCOS '03, Mumbai-India, January 3-8 2003.
To appear in a special issue of Praman
A twisted conformal field theory description of the Quantum Hall Effect
We construct an effective conformal field theory by using a procedure which
induces twisted boundary conditions for the fundamental scalar fields. That
allows to describe a quantum Hall fluid at Jain hierarchical filling,
nu=m/(2pm+1), in terms of one charged scalar field and m-1 neutral ones. Then
the resulting algebra of the chiral primary fields is U(1)xW_m. Finally the
ground state wave functions are given as correlators of appropriate composite
fields (a-electrons).Comment: 11 pages, plain Late
Topological order in Josephson junction ladders with Mobius boundary conditions
We propose a CFT description for a closed one-dimensional fully frustrated
ladder of quantum Josephson junctions with Mobius boundary conditions, in
particular we show how such a system can develop topological order. Such a
property is crucial for its implementation as a "protected" solid state qubit.Comment: 14 pages, 3 figures, to appear in JSTA
Environmental sustainability approaches and positive energy districts: A literature review
During the last decade, increasing attention has been paid to the emerging concept of Positive Energy Districts (PED) with the aim of pushing the transition to clean energy, but further research efforts are needed to identify design approaches optimized from the point of view of sustainable development. In this context, this literature review is placed, with a specific focus on environmental sustainability within innovative and eco-sustainable districts. The findings show that some sustainability aspects such as sustainable food, urban heat islands mitigation and co-impacts, e.g., green gentrification, are not adequately assessed, while fragmented thinking limits the potential of circularity. In this regard, targeted strategies should be developed. On the other hand, the Key Performance Indicators framework needs some integrations. In this direction, indicators were suggested, among those defined in the Sustainable Development Agenda, the main European standards and initiatives and the relevant literature experiences. Future outlooks should be directed to-wards: the harmonization of the Life Cycle Assessment in PEDs with reference to modeling assump-tions and analysis of multiple impacts; the development of dynamic environmental analyses taking into account the long-term uncertainty due to climate change, data availability and energy decar-bonization; the combination of Life Cycle Assessment and Key Performance Indicators based tech-niques, from a holistic thinking perspective, for a comprehensive design environment and the analysis of the contribution of energy flexibility approaches on the environmental impact of a project
IL RUOLO DEL PATRIMONIO NEL PROGETTO URBANO MARSIGLIA E TUNISI, CITT\uc1 DEL MEDITERRANEO
La ricerca si occupa del rapporto tra le nuove modalit\ue0 di trasformazione della citt\ue0 mediterranea e le nuove strategie di rigenerazione e valorizzazione del patrimonio materiale e immateriale. Comprendere qual \ue8 il ruolo del patrimonio nel processo di trasformazione e crescita della citt\ue0 mediterranea, attraverso la pratica del progetto urbano, \ue8 la questione principale della tesi, che si inserisce nel campo delle ricerche sulle modalit\ue0 di trasformazione della citt\ue0 contemporanea. La ricerca si interroga, inoltre, su quale sia il rapporto che oggi lega il patrimonio e la sviluppo sostenibile, ambiti non pi\uf9 antitetici ma complementari, in una costruzione reciproca di simbologie e differenze, che d\ue0 frutto alla contaminazione e alla loro ridefinizione.
Questa relazione tra patrimonio e progetto urbano ha permesso, attraverso il sostegno degli esempi selezionati, di indentificare alcuni dei temi federatori che riguardano la valorizzazione e la trasformazione del patrimonio che \ue8 possibile ritrovare nei progetti urbani sostenibili avviati nel corso dell\u2019ultimo decennio: l\u2019obsolescenza, le aree dismesse e le nuove centralit\ue0, insieme al re-cycling e alla trasformazione, il patrimonio architettonico e il tessuto urbano nella citt\ue0 storica. Nello specifico, tali temi sono stati indagati attraverso l\u2019approfondimento di due citt\ue0 nel bacino Nord e Sud del Mediterraneo: Marsiglia e Tunisi. La citta di Marsiglia, \ue8 stata selezionata perch\ue9 da alcuni anni si svolge il progetto Eurom\ue9diterran\ue9e in cui \ue8 indagato, in particolare, il tema dell\u2019obsolescenza delle architetture e delle aree dismesse, convertite in centralit\ue0 urbane. La citt\ue0 di Tunisi, \ue8 stata individuata per i progetti emblematici sul patrimonio materiale e immateriale realizzati dall\u2019Association de Sauvegarde de la M\ue9dina (ASM) nella citt\ue0 storica.La recherche s\u2019occupe du rapport entre les nouvelles modalit\ue9s de transformation de la ville m\ue9diterran\ue9enne et les nouvelles strat\ue9gies de r\ue9g\ue9n\ue9ration et de valorisation du patrimoine mat\ue9riel et immat\ue9riel. Comprendre le r\uf4le du patrimoine dans le processus de transformation de la ville m\ue9diterran\ue9enne, \ue0 travers la pratique du projet urbain, est la question principale de la th\ue8se qui se place dans le cadre des recherches sur les modalit\ue9s de transformation de la ville contemporaine. La recherche analyse, \ue9galement, la relation qui existe de nos jours entre le patrimoine et le d\ue9veloppement durable, notions qui ne sont plus antith\ue9tiques mais compl\ue9mentaires, dans une construction r\ue9ciproque de symbologies et de diff\ue9rences, conduisant \ue0 leur red\ue9finition.
Cette relation entre patrimoine et projet urbain retrac\ue9e ici, \ue0 l\u2019aide des projets et des r\ue9alisations s\ue9lectionn\ue9es, a permis d\u2019identifier certains th\ue8mes f\ue9d\ue9rateurs concernant la valorisation et la transformation du patrimoine, qu\u2019il est possible de retrouver dans les projets urbains durables lanc\ue9s au cours de cette derni\ue8re d\ue9cennie : l\u2019obsolescence, les lieux d\ue9saffect\ue9s et les nouvelles centralit\ue9s, le re-cycling, le patrimoine architectural et le tissu urbain historique. Pr\ue9cis\ue9ment, ces th\ue8mes ont \ue9t\ue9 analys\ue9s \ue0 travers l\u2019\ue9tude de deux villes dans le bassin du Nord et du Sud de la M\ue9diterran\ue9e : Marseille et Tunis. Marseille a \ue9t\ue9 choisie pour le Projet Eurom\ue9diterran\ue9e, dans lequel a \ue9t\ue9 approfondi le th\ue8me de l\u2019obsolescence de l\u2019architecture et des lieux d\ue9saffect\ue9s, transform\ue9s en nouvelles centralit\ue9s. Tunis a \ue9t\ue9 individu\ue9e pour les projets embl\ue9matiques sur le patrimoine \ue9labor\ue9s par l\u2019Association de Sauvegarde de la M\ue9dina (ASM) dans la ville historique
Functional neurological disorders as seen by a cohort of general practitioners in northern italy: Evidence from an online survey
General practitioners (GPs) provide primary care and advise their patients on which diagnostic and therapeutic pathways they judge most appropriate. For patients with functional neurological disorders (FND), receiving a proper explanation of diagnosis by their GP from the very beginning may drastically improve prognosis. Novel approaches to the diagnosis and treatment of FND have important implications for effective management. The aim of this study was to investigate Italian GP opinion and knowledge about FND in light of new approaches to the illness. To do this, we evaluated the responses to a 13-item web-based survey completed by 133 GPs practicing in northern Italy. Psychological terms to describe FND were more frequently used than functional neurological disorder and mental illness was considered an important predictor of diagnosis. Referral to a neurologist rather than to a psychiatrist was largely preferred, while physiotherapy consultation was seldom recognized as a valuable approach to treating FND. Overall, the survey findings suggest that knowledge about novel approaches to FND is somewhat lacking. Currently, GPs appear to be transitioning from a classical psychological view of the disorder toward a more modern conceptualization, in which neurobiological, psychological, and social factors all play an important role. Professional education during this transition would be an advantageous way to optimize physician management of FND and to enhance diagnosis, explanation, and management across primary and secondary care pathways
Fractional D-branes and their gauge duals
We study the classical geometry associated to fractional D3-branes of type
IIB string theory on R^4/Z_2 which provide the gravitational dual for N=2 super
Yang-Mills theory in four dimensions. As one can expect from the lack of
conformal invariance on the gauge theory side, the gravitational background
displays a repulson-like singularity. It turns out however, that such
singularity can be excised by an enhancon mechanism. The complete knowledge of
the classical supergravity solution allows us to identify the coupling constant
of the dual gauge theory in terms of the string parameters and to find a
logarithmic running that is governed precisely by the beta-function of the N=2
super Yang-Mills theory.Comment: Latex file, 15 pages; final version published in JHE
Visible—Light Driven Systems: Effect of the Parameters Affecting Hydrogen Production through Photoreforming of Organics in Presence of Cu2O/TiO2 Nanocomposite Photocatalyst
Wrapped Magnetized Branes: Two Alternative Descriptions?
We discuss two inequivalent ways for describing magnetized D-branes wrapped N
times on a torus T^2. The first one is based on a non-abelian gauge bundle
U(N), while the second one is obtained by means of a Narain T-duality
transformation acting on a theory with non-magnetized branes. We construct in
both descriptions the boundary state and the open string vertices and show that
they give rise to different string amplitudes. In particular, the description
based on the gauge bundle has open string vertex operators with momentum
dependent Chan-Paton factors.Comment: 60 pages, LaTe
Point-like topological defects in bilayer quantum Hall systems
Following a suggestion given in Phys. Lett. B 571 (2003) 250, we show how a
bilayer Quantum Hall system at fillings nu =m/pm+2 can exhibit a point-like
topological defect in its edge state structure. Indeed our CFT theory for such
a system, the Twisted Model (TM), gives rise in a natural way to such a feature
in the twisted sector. Our results are in agreement with recent experimental
findings (cond-mat/0503478) which evidence the presence of a topological defect
in the bilayer system.Comment: 9 pages, 3 figure
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